KTM 505sx-f rebuild

[cods4]

So my KTM 505sx-f has been sitting in the garage for a year or two with just about 100hrs on it and I have finally decided to tear it apart and start on rebuilding it. Got the heads off and ordered the first lot of parts (piston, rings and head gasket kit). While i'm in there what else should I be doing? Is it worth taking the cylinder and heads to an engine machine shop to get them all cleaned up and tested for roundness, flatness, cracks etc and cleaned?

When I was undoing the head one of the studs came loose at the bottom where it screws into the case (instead of the nut coming loose) so I believe I should replace all the head studs, nuts and washers instead of just replacing the one with the nut stuck on. Does that sound right? Or can I get away with reusing the old ones?

Valve clearances are ok and havent changed in the last 30 hours or so since Ive had the bike so I am not expecting to have to change valves or valve springs etc.

[SVboy]

While the head is off, get your machine shop to dismantle it and check valve faces and seats. New valves might be a good idea while it is torn down.

[cods4]

While the head is off, get your machine shop to dismantle it and check valve faces and seats. New valves might be a good idea while it is torn down.

Thanks for the suggestion, I would like to have that done, however unfortunately for a set of valves and valve springs I would be looking at $850 USD, plus GST etc, so they would be out of the question. Valves clearances haven't moved in the last 20 hours so I am not really concerned about them.

Check out the link for some pics of the teardown. The only wear I have noticed are some very minor marks on the piston skirts and the corresponding cylinder wall. And the compression ring end gap was around 1.7mm when the spec allows for up to 0.7mm. The oil ring was about the same.

http://imgur.com/a/ByKhU